Stem cells have the ability to differentiate into multiple diverse cell types and self-renew to produce more stem cells. In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues, including fetal tissues. Generally, adult stem cells are lineage-restricted (multipotent) and are generally referred to by their tissue origin. Multipotent stem cells have been isolated from several tissues including bone marrow, peripheral blood, adipose tissue, liver, skin, amniotic fluid, placenta and umbilical cord. Included among such cells are mesenchymal stem cells, adipose-derived stem cells, and endothelial stem cells. Human mesenchymal stem cells (MSC) have been shown to differentiate into multiple mesoderm-type lineages, including chondrocytes, osteoblasts, and adipocytes and into ectodermal and endodermal origin. Because of their ability for self-renewal and multilineage differentiation potential, multipotent stem cells are useful for cell-based therapies and tissue engineering applications. Multipotent stem cells also exhibit immunomodulatory and paracrine effects.